1. Field of the Invention
The present invention relates to an ink cartridge for an ink-jet printer, and, more particularly, to an ink cartridge for an ink-jet printer in which ink channels from three ink chambers to one printhead are fabricated in a unitary body in an ink cartridge body.
2. Description of the Related Art
In general, an ink cartridge for an ink-jet printer stores ink and ejects ink droplets through a printhead in order to print an image of a predetermined color on paper. In the ink cartridge, it is very important to arrange ink channels to be connected from ink chambers, in which ink of three colors is stored, to a printhead, so that the ink moves from the ink chambers to the printhead during a color printing operation. In a conventional method of fabricating an ink cartridge, an ink cartridge having multiple chambers is fabricated by combining a plurality of plastic components.
However, in the conventional method for fabricating an ink cartridge by assembling a plurality of components, the number of components and the number of assembling processes are increased. As a result, fabrication costs increase.
In order to solve this problem, an ink cartridge formed as a unitary body is disclosed in U.S. Pat. No. 6,260,961.
Referring to FIG. 1, an ink cartridge 10 includes first, second, and third chambers 13, 14, and 15, which are separated by “T”-shaped interior walls 11 and 12. Each of the first, second, and third chambers 13, 14, and 15 stores ink of a different color. Reference numeral 16 denotes a sealing member for sealing an opening into which a side core is inserted for injection molding of the unitary body ink cartridge 10.
FIG. 2 is a cross-sectional view illustrating the lower structure of a second or third chamber of FIG. 1. Ink stored in the second chamber 14 is supplied to an ink feed slot 24 through an ink outlet port 22 and a filter (not shown) installed on a standpipe 21. That is, ink stored in the second chamber 14 flows along an ink flow path indicated by an arrow 23. A printhead is installed under the ink outlet port 22. The printhead receives ink supplied from the ink outlet port 22, and ejects ink, through nozzles (not shown), in the shape of ink droplets.
FIG. 3 is a cross-sectional view illustrating the lower structure of the first chamber 13.
Referring to FIGS. 1 through 3, ink stored in the first chamber 13 passes through an opening 33 and a vertical ink channel 34 in a standpipe 31, and is supplied to an ink feed slot 35. Ink passing through the ink feed slot 35 is supplied to the nozzles of the printhead.
In a conventional ink cartridge 10 having the above structure, in order to injection mold the ink cartridge 10 as a unitary body, a side core, which is a mold for molding the ink flow path including an ink channel formed under the ink cartridge 10, is required. The side core has a slanted structure so as to be easily inserted into or removed from the mold forming the ink cartridge 10. A sealing member 16 is sealed in an opening of the ink cartridge 10, through which the side core is inserted into or removed from, by adhesive or by ultrasonic welding. If the sealing member 16 is not precisely combined with the ink cartridge 10, interference with interconnection and contact points of a flexible printed circuit (FPC) (not shown) attached on the printhead of the ink cartridge 10 occurs. Thus, an operation of transmitting an electrical signal to the printhead is disturbed. As a result, printing quality is lowered.
In addition, when inks of different colors are supplied to the printhead through two long ink flow paths 23 from the second and third chambers 14 and 15 as in the conventional ink cartridge, the sealing member 16 should prevent the inks from leaking out of the ink flow paths 23, and should prevent leaks between the adjacent ink flow paths 23. Thus, the internal structure of the side core and the sealing member 16 becomes complicated. In addition, when sealing using the sealing member 16 is incomplete, color mixture may occur due to leaks between the ink flow paths 23.